aom/examples/decode_with_drops.c

153 строки
4.4 KiB
C

/*
* Copyright (c) 2010 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
// Decode With Drops Example
// =========================
//
// This is an example utility which drops a series of frames, as specified
// on the command line. This is useful for observing the error recovery
// features of the codec.
//
// Usage
// -----
// This example adds a single argument to the `simple_decoder` example,
// which specifies the range or pattern of frames to drop. The parameter is
// parsed as follows:
//
// Dropping A Range Of Frames
// --------------------------
// To drop a range of frames, specify the starting frame and the ending
// frame to drop, separated by a dash. The following command will drop
// frames 5 through 10 (base 1).
//
// $ ./decode_with_drops in.ivf out.i420 5-10
//
//
// Dropping A Pattern Of Frames
// ----------------------------
// To drop a pattern of frames, specify the number of frames to drop and
// the number of frames after which to repeat the pattern, separated by
// a forward-slash. The following command will drop 3 of 7 frames.
// Specifically, it will decode 4 frames, then drop 3 frames, and then
// repeat.
//
// $ ./decode_with_drops in.ivf out.i420 3/7
//
//
// Extra Variables
// ---------------
// This example maintains the pattern passed on the command line in the
// `n`, `m`, and `is_range` variables:
//
//
// Making The Drop Decision
// ------------------------
// The example decides whether to drop the frame based on the current
// frame number, immediately before decoding the frame.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "vpx/vp8dx.h"
#include "vpx/vpx_decoder.h"
#include "../tools_common.h"
#include "../video_reader.h"
#include "./vpx_config.h"
static const char *exec_name;
void usage_exit(void) {
fprintf(stderr, "Usage: %s <infile> <outfile> <N-M|N/M>\n", exec_name);
exit(EXIT_FAILURE);
}
int main(int argc, char **argv) {
int frame_cnt = 0;
FILE *outfile = NULL;
vpx_codec_ctx_t codec;
const VpxInterface *decoder = NULL;
VpxVideoReader *reader = NULL;
const VpxVideoInfo *info = NULL;
int n = 0;
int m = 0;
int is_range = 0;
char *nptr = NULL;
exec_name = argv[0];
if (argc != 4)
die("Invalid number of arguments.");
reader = vpx_video_reader_open(argv[1]);
if (!reader)
die("Failed to open %s for reading.", argv[1]);
if (!(outfile = fopen(argv[2], "wb")))
die("Failed to open %s for writing.", argv[2]);
n = strtol(argv[3], &nptr, 0);
m = strtol(nptr + 1, NULL, 0);
is_range = (*nptr == '-');
if (!n || !m || (*nptr != '-' && *nptr != '/'))
die("Couldn't parse pattern %s.\n", argv[3]);
info = vpx_video_reader_get_info(reader);
decoder = get_vpx_decoder_by_fourcc(info->codec_fourcc);
if (!decoder)
die("Unknown input codec.");
printf("Using %s\n", vpx_codec_iface_name(decoder->codec_interface()));
if (vpx_codec_dec_init(&codec, decoder->codec_interface(), NULL, 0))
die_codec(&codec, "Failed to initialize decoder.");
while (vpx_video_reader_read_frame(reader)) {
vpx_codec_iter_t iter = NULL;
vpx_image_t *img = NULL;
size_t frame_size = 0;
int skip;
const unsigned char *frame = vpx_video_reader_get_frame(reader,
&frame_size);
if (vpx_codec_decode(&codec, frame, (unsigned int)frame_size, NULL, 0))
die_codec(&codec, "Failed to decode frame.");
++frame_cnt;
skip = (is_range && frame_cnt >= n && frame_cnt <= m) ||
(!is_range && m - (frame_cnt - 1) % m <= n);
if (!skip) {
putc('.', stdout);
while ((img = vpx_codec_get_frame(&codec, &iter)) != NULL)
vpx_img_write(img, outfile);
} else {
putc('X', stdout);
}
fflush(stdout);
}
printf("Processed %d frames.\n", frame_cnt);
if (vpx_codec_destroy(&codec))
die_codec(&codec, "Failed to destroy codec.");
printf("Play: ffplay -f rawvideo -pix_fmt yuv420p -s %dx%d %s\n",
info->frame_width, info->frame_height, argv[2]);
vpx_video_reader_close(reader);
fclose(outfile);
return EXIT_SUCCESS;
}